1. Field of the Invention
The present invention generally relates to a combination hydraulic cylinder and shock absorber adapted for use in combination with a pivotally supported, elongated, generally horizontal spray boom to adjust the angular position of the boom about a horizontal axis and to cushion, dampen and control vertical swinging or oscillatory movement of the boom due to forces exerted on the boom by a supporting vehicle as it traverses uneven terrain such as when applying flowable material from the spray boom onto a land surface.
2. Description of the Prior Art
Spray booms are utilized for applying flowable material such as liquid fertilizer, water, or the like, to various land surfaces for increasing crop yield from the soil. Such devices include a powered vehicle, towed vehicle, or the like, and an elongated boom or elongated booms attached thereto generally in a cantilevered fashion with a plurality of discharge nozzles being spaced longitudinally along the boom or booms. Usually, the boom is horizontally oriented and frequently, the end of the boom attached to the vehicle is pivotally supported for swinging movement in a vertical plane about a fore-and-aft horizontal axis in order to adjust the position of the boom in a vertical plane. Due to the elongated nature of the boom, it is subject to considerable vertical oscillation, bouncing or swinging movement due to the vehicle passing over an uneven terrain especially when considering the resilient characteristics of the elongated boom itself and the relatively stiff springing of the vehicle so that when the vehicle wheel engages a sudden depression or projection in the ground surface, the boom will be subjected to considerable vertical swinging movement. If the boom is rigidly fixed in adjusted position by some type of clamp or hold-down, that portion of the boom outwardly of the hold-down point will still flex and swing with the hold-down point becoming a fulcrum point for the cantilevered portion of the boom which, under some conditions, results in bending or breakage of the boom due to extensive flexing of the boom about the stationary hold-down point.